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Abstract Medical adhesives are vital for securing wearable sensors, wound dressings, and critical medical devices. These adhesives must balance strong adhesion with patient comfort, especially when used over extended periods. Adhesives that maintain their efficacy for more than two weeks are essential for continuous monitoring devices, as they enhance diagnostic accuracy and reduce dressing changes, minimizing patient discomfort and infection risk. However, current long-wear adhesives often use aggressive acrylics that can cause skin injuries. To overcome these limitations, we developed an advanced ThermoTape offering temperature-responsive properties with a polyurethane backing for more than 14 days of wear. A double transfer coating process fabricated PU-ThermoTape, with surface morphology characterized using Atomic Force Microscopy. Differential Scanning Calorimetry and thermography determined the optimal removal window. Peeling strength tests were conducted at room and elevated temperatures to assess performance. In vitro, PU-ThermoTape displayed an average peeling strength of 0.3 N/mm at 25 °C, decreasing by 75% when heated to 45°C, with an optimal removal window of approximately 2.5 minutes. The tape demonstrated excellent skin conformity with its polyurethane backing. In a 14-day wearability study with seven volunteers, PU-ThermoTape outperformed Tegaderm, maintaining temperature-responsiveness and allowing unrestricted daily activities throughout. PU-ThermoTape provides robust adhesion, high skin conformity, and facilitates gentle removal after brief warming, positioning it as a versatile adhesive suitable for various applications with different duration requirements. 

Luminescent solar concentrators (LSCs) can concentrate direct and diffuse solar radiation spatially and energetically to help reduce the overall area of solar cells needed to meet current energy demands. LSCs require luminophores that absorb large fractions of the solar spectrum, emit photons into a light-capture medium with high photoluminescence quantum yields (PLQYs), and do not absorb their own photoluminescence. Luminescent nanocrystals (NCs) with near or above unity PLQYs and Stokes shifts large enough to avoid self-absorption losses are well-suited to meet these needs. In this work, we describe LSCs based on quantum-cutting Yb 3+ :CsPb(Cl 1−x Br x ) 3 NCs that have documented PLQYs as high as ∼200%. Through a combination of solution-phase 1D LSC measurements and modeling, we demonstrate that Yb 3+ :CsPbCl 3 NC LSCs show negligible intrinsic reabsorption losses, and we use these data to model the performance of large-scale 2D LSCs based on these NCs. We further propose a new and unique monolithic bilayer LSC device architecture that contains a Yb 3+ :CsPb(Cl 1−x Br x ) 3 NC top layer above a second narrower-gap LSC bottom layer ( e.g. , based on CuInS 2 NCs), both within the same waveguide and interfaced with the same Si PV for conversion. We extend the modeling to predict the flux gains of such bilayer devices. Because of the exceptionally high PLQYs of Yb 3+ :CsPb(Cl 1−x Br x ) 3 NCs, the optimized bilayer device has a projected flux gain of 63 for dimensions of 70 × 70 × 0.1 cm 3 , representing performance enhancement of at least 19% over the optimized CuInS 2 LSC alone.